Enzymatic hydrolysis is an important step for the biomass-based biofuel production. Enzymatic hydrolysis eliminates the need for large quantities of acid and the neutralization of this acid, but commercial cellulase enzyme costs are currently high, and enzyme attack of the cellulose and hemicellulose polymers can be slow. On the other hand, many details of enzymatic activity are still poorly understood, although the mechanisms of hydrolysis and the relationship between the structure and function of various cellulases have been extensively studied.
The enzymatic hydrolysis of lignocellulosic substrates is strongly affected by end-product inhibition and enzyme features. Therefore, biomass hydrolysis is directly or indirectly related to the substrate availability, end product accumulation and/or enzyme inhibitors generated during or after biomass pretreatment which hinders the specific activities of cellulases on their respective substrates. Low specific catalyst activity on substrates limits the effectiveness of hydrolysis.